Move CLUSTER_STACK_NAME to the common variables

The cluster name is pretty much required by all recipes, hence
it makes more sense to have it in the common variables.

Change-Id: I2e833f93b0721fe9860acfd21ffb8bdf6cc689b1
diff --git a/common.env b/common.env
index ce79fc7..bec27a4 100644
--- a/common.env
+++ b/common.env
@@ -25,3 +25,6 @@
 
 # Nested templates bucket
 TEMPLATE_BUCKET_NAME=aws-gerrit-cf-templates
+
+# Elastic Container Service
+CLUSTER_STACK_NAME:=$(AWS_PREFIX)-cluster
diff --git a/dual-master/setup.env.template b/dual-master/setup.env.template
index 5917586..c340d14 100644
--- a/dual-master/setup.env.template
+++ b/dual-master/setup.env.template
@@ -1,4 +1,3 @@
-CLUSTER_STACK_NAME:=$(AWS_PREFIX)-cluster
 CLUSTER_DESIRED_CAPACITY:=3
 CLUSTER_INSTANCE_TYPE:=m4.2xlarge
 SERVICE_MASTER1_STACK_NAME:=$(AWS_PREFIX)-service-master-1
diff --git a/master-slave/setup.env.template b/master-slave/setup.env.template
index 732448e..32fe85e 100644
--- a/master-slave/setup.env.template
+++ b/master-slave/setup.env.template
@@ -1,4 +1,3 @@
-CLUSTER_STACK_NAME:=$(AWS_PREFIX)-cluster
 CLUSTER_DESIRED_CAPACITY:=1
 CLUSTER_INSTANCE_TYPE:=m4.10xlarge
 SERVICE_MASTER_STACK_NAME:=$(AWS_PREFIX)-service-master
diff --git a/single-master/setup.env.template b/single-master/setup.env.template
index c907ce8..2d15394 100644
--- a/single-master/setup.env.template
+++ b/single-master/setup.env.template
@@ -1,4 +1,3 @@
-CLUSTER_STACK_NAME:=$(AWS_PREFIX)-cluster
 SERVICE_STACK_NAME:=$(AWS_PREFIX)-service
 CLUSTER_INSTANCE_TYPE:=m4.10xlarge
 DNS_ROUTING_STACK_NAME:=$(AWS_PREFIX)-dns-routing